The simulation analysis was performed to enhance the efficiency of Sb2S3 solar cells using the SCAPS-1D software. The compound was used as the absorber layer in the solar cell. The simulation was conducted to verify the efficiency and accuracy of the results obtained from the program. The results were found to be in agreement with the practical results. The original cell’s efficiency was 11.47% with a fill factor of 61.18%, and after the simulation, the efficiency was found to be 11.43% with a fill factor of 61.2%. To enhance the efficiency of the solar cell, a reflective background layer (BSL) was added. Different BSL layers were examined, including SnS, Si, CIGS, CZTSSe, and , and the best reflective layer was found to be . The solar cell structure was designed as follows: . After adding the reflective layer, the efficiency of the solar cell was found to be 20.59% with a fill factor of 87.53%. The results suggest that adding reflective layers to solar cells can enhance their performance and increase their efficiency.